1. Technical Field
This invention relates to the field of international dialing services and, more particularly, to a method and apparatus for automatically redialing an international call in the event of predetermined call failures or the timeout of a timer.
2. Description of the Related Arts
U.S. patent application Ser. No. 08/919,000, filed Aug. 27, 1997 (Attorney Docket No. Fahrer 7-1-1-1-1-3) describes an international redial system in which the cause of an international call failure is identified according to International Telecommunications Union (I.T.U.) standards. When an international call is placed, modern foreign networks return data representative of one of several reasons for a failure to complete an international call. According to the ITU-T recommendations, cause failure data may represent one of up to 127 individual causes for the failure of an international call, when the call does not go through. For example, cause value code number 17 relates to "user busy, "that is, the called party is presently on their line and the line is busy for that reason. If there is a network busy problem, then a cause value code 42 is returned representing "switching equipment congestion." If the caller dials an invalid number, a cause code value of 28 is returned for "invalid number format."
Different countries have chosen to implement ITU-T recommendations in different ways. For example, the United Kingdom uses the ISUP (the Integrated Services Digital Network User Part) signaling system to indicate a cause failure reason as a "cause" value number. Other countries such as France use the TUP (Telephone User Part) signaling system in which reasons for call failures are indicated by the generation of an appropriate "signal code." Still other countries use the R2 (Register Signaling 2) signaling system in which "B-signal" codes represent reasons for call failures. All of these may be translated into an indicative signal code. Hereinafter, any one or any other data indicative of a reason for the failure of an international call shall be referred to herein as "unsuccessful call reason information."
It is also described in the '000 application that an international service is presently available from AT&T known as AT&T International Redial (AIR) service. AT&T long distance customers may presubscribe to AIR service. When a subscriber is unsuccessful in completing an international call, AT&T can check to be sure the subscriber has presubscribed and then prompt the subscriber: "If you would like to use AT&T International Redial service, please press *234." If the caller presses *234, the redial service automatically attempts to redial the call, for example, up to ten times in a half hour period. While the caller is waiting for the call to go through, the caller may occupy themselves with other tasks. With AIR service, the caller does not have to place the call until the call goes through, the network does, and calls the caller back when the call is completed.
AT&T previously has relied on the expiration of a timer to determine when to offer *234 international redial service. For example, if a call does not go through before the timer expires, the toll network assumes that there is network congestion. The '000 application describes an international redial service that is based on unsuccessful call reason information as defined above that is returned from the foreign network--such as user busy code 17 or network busy code 42. This saves having to rely on a timer. Also, if cause code value 28, representing an invalid number, is returned, the international redial service can be inhibited.
In the United States and on local calls, traditionally, the calling party, in the event of network congestion, receives a domestic re-order (fast busy signal) or a prompt: "All circuits are busy now; please try your call again later." Of course, a caller hearing such a message is encouraged to place the call themselves at a later time, wasting their time, in hopes that at the later time when they try the call again, the call will go through.
Studies have shown that for national and international calls, in the event of network congestion, there is a real probability that, upon the next immediate attempt, the call will go through. Consequently, prompting the user to try again later may be counterproductive and encourage the caller not to try again. Moreover, the user may forget to make the call later.
Also, once the caller has placed a call the first time, there is an opportunity that revenue to the toll service provider will be lost if the caller does not get through. Moreover, the attempted call has already tied up local exchange carrier and toll facilities in the attempt from which no revenue will result from the call failure.
According to U.S. Pat. No. 5,539,809, there are a number of alternative messages that may be played to a caller during the period of time an international caller is awaiting the called party to answer. These include time-of-day in country announcements and the like that may be country and area code specific. These announcements may compete with announcements made by a toll carrier during a call as described above such as all circuits busy announcements. Consequently, it is also useful that any solution to the problems of failing to complete an international call discussed above that all announcements that may be required are prioritized and coordinated.
Consequently, it is an object of the present invention to increase the likelihood of realizing revenues from a caller's placing an international call. It is a further object to assist the user in making an international call by making an international call as caller friendly and as automatic for the caller as possible.